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Volume 31(3): 1–380 METAMORPHOSIS ISSN 1018–6490 (PRINT) ISSN 2307–5031 (ONLINE) LEPIDOPTERISTS’ SOCIETY OF AFRICA An overview of Lepidoptera-host-parasitoid associations for southern Africa, including an illustrated report on 2 370 African Lepidoptera-host and 119 parasitoid-Lepidoptera associations Published online: 3 November 2020 Hermann S. Staude1*, Marion Maclean1, Silvia Mecenero1,2, Rudolph J. Pretorius3, Rolf G. Oberprieler4, Simon van Noort5, Allison Sharp1, Ian Sharp1, Julio Balona1, Suncana Bradley1, Magriet Brink1, Andrew S. Morton1, Magda J. Botha1, Steve C. Collins1,6, Quartus Grobler1, David A. Edge1, Mark C. Williams1 and Pasi Sihvonen7 1Caterpillar Rearing Group (CRG), LepSoc Africa. [email protected], [email protected], [email protected], [email protected], [email protected], [email protected], [email protected], [email protected], [email protected], [email protected], [email protected], [email protected] 2Centre for Statistics in Ecology, Environment and Conservation, Department of Statistical Sciences, University of Cape Town, South Africa. [email protected] 3Department of Agriculture, Faculty of Health and Environmental Science. Central University of Technology, Free State, Bloemfontein, South Africa. [email protected] 4CSIRO National Insect Collection, G. P. O. Box 1700, Canberra, ACT 2701, Australia. [email protected] 5Research & Exhibitions Department, South African Museum, Iziko Museums of South Africa, Cape Town, South Africa and Department of Biological Sciences, University of Cape Town, Rondebosch, South Africa. [email protected] 6African Butterfly Research Institute (ABRI), Nairobi, Kenya. [email protected] 7Finnish Museum of Natural History, Helsinki, Finland. [email protected] * Corresponding author Copyright © Lepidopterists’ Society of Africa Abstract: We present an overview of the known host associations of larval Lepidoptera for southern Africa, based on a database of 11 628 rearings, including all Caterpillar Rearing Group (CRG) records and other published records. Rearings per Lepidoptera family show some bias in the rearing effort towards the more conspicuous families, ectophagous groups and non-detritus-feeders but in general follow species diversity. Recorded Lepidoptera host associations per host family for southern Africa are shown. Data analyses revealed the following general trends: of the 20 most reared species 13 are polyphagous; Fabaceae are the most utilised plant family with 2 122 associations, followed by Asteraceae (600), Malvaceae (564) and Anacardiaceae (476); 98.8 % of hosts are vascular plants; and of the 19 most utilised host species 18 are common trees or shrubs. We discuss possible reasons behind these trends, particularly the high utilisation of Fabaceae and the widespread use of trees and shrubs as hosts. We compare recorded host species numbers with species diversity for the 19 most recorded host families and discuss possible reasons for the low utilisation of four plant families with an exceptionally low percentage of Lepidoptera host species / plant host species diversity. All Lepidoptera families for which more than 100 rearings have been recorded (21 families) utilise one (or two in the case of Pyralidae, Nolidae and Hesperiidae) plant family exponentially more than any of the other families, with resulting histograms forming hyperbolic curves, as are typical of distributions of taxonomic assemblages in nature. We calculate an exponential factor to quantify this phenomenon and show that for all 21 Lepidoptera families one host family is utilised 6–33 times more than the average use of other host families. In this paper, the larvae and adults of 953 African, mostly South African, Lepidoptera species reared by the CRG between January 2016 and June 2019 are illustrated together with pertinent host information. 119 Lepidoptera-parasitoid associations are reported, comprising seven hymenopteran families and one dipteran family. With the current data release, larval host association records are now available for 2 826 Lepidoptera species in the southern African subregion, covering about 25 % of the described fauna. Key words: Lepidoptera, Hymenoptera, Diptera, caterpillar, larva, moth, butterfly, South Africa, Africa, Afrotropical region, pupa, host, life-history, host-use, host-specialisation, parasitoid. Citation: Staude, H.S., Maclean, M., Mecenero, S., Pretorius, R.J., Oberprieler, R.G., Van Noort, S., Sharp, A., Sharp, I., Balona, J., Bradley, S., Brink, M., Morton, A.S., Botha, M.J., Collins, S.C., Grobler, Q., Edge, D.A., Williams, M.C. & Sihvonen, P. (2020). An overview of Lepidoptera-host-parasitoid associations for southern Africa, including an illustrated report on 2 370 African Lepidoptera-host and 119 parasitoid-Lepidoptera associations. Metamorphosis 31(3): 1–380. INTRODUCTION Plants, insect herbivores and their arthropod parasitoids and predators constitute over 75 % of all multicellular diversity of terrestrial life on earth (Price, 2002). All three Received: 15 August 2020 are crucial for ecosystem functioning. The effect of Published: 3 November 2020 disruption of the ecological balance at these trophic levels Copyright: This work is licensed under the Creative Commons can be clearly seen in the devastating impact of alien Attribution-NonCommercial-NoDerivs 3.0 Unported License. To invasive species across the globe (Vilá et al., 2011). Yet view a copy of this license, send a letter to Creative Commons, Second Street, Suite 300, San Francisco, California, 94105, USA, even fundamental knowledge on ecological interactions at or visit: http://creative commons.org/licenses/by-nc-nd/3.0/ these three trophic levels for the Afrotropical region is largely lacking. Staude et al. / Metamorphosis 31(3): 1–380 2 A compilation of Lepidoptera-host associations recorded not included in the previous papers for various reasons for southern Africa (including all published records to (e.g. late submission to the project). date) conducted in 2012 registered such associations for less than 7 % of the Lepidoptera species in southern Comprehensive details of the methods employed by the Africa and for only a handful of Lepidoptera-parasitoid CRG were published in Staude et al. (2016a), which associations (Staude & Kroon, 2012). To address this remain the same for this publication (unless otherwise problem, at least for Lepidoptera-host-parasitoid stated below), and only a shortened version is presented interactions, the Lepidopterists’ Society of Africa here. (LepSoc Africa) launched a successful citizen science project called the Caterpillar Rearing Group (CRG), Terminology details of which can be found in Staude et al. (2016a). The The terms ‘caterpillar’ and ‘larva’ are used CRG compiles selected rearing data into master lists, each interchangeably in this article, although they are not fully representing a major Lepidoptera taxonomic group. The synonymous. ‘Larva’ (plural: larvae) is the technical term main purpose of the master lists is to create a vehicle by for the life stage of any holometabolous insect between which this large and growing set of life-history data can egg and pupa, whereas ‘caterpillar’ is a vernacular term become accessible to other users, from scientists to for the (generally free-living) larvae of moths and conservationists, naturalists and other parties. butterflies (Lepidoptera) as well as those of sawflies Parasitoids are defined by their behaviour of ultimately (Hymenoptera). The rearing efforts of the CRG do not killing their hosts (Price, 1975; Godfray & Godfray, 1994; cover the caterpillars of sawflies, however. Mills, 2009; Quicke, 2015). It is usually the larval stage of The term ‘host’ is relative and depends on the context in the parasitoid that attacks the host invertebrate (usually which it is being used in the text. A Lepidoptera ‘host’ the immature stages), whereas the adults are free-living refers to the source organism of the food used by the (Vinson, 1976; Godfray & Godfray, 1994). In contrast to Lepidoptera larva. This is usually a living plant, but it may true parasites, which do not kill the host, parasitoids only also be other living organisms or their detritus. A require a single host to develop into adults (Price, 1975; parasitoid ‘host’ is the lepidopteran taxon from which the Godfray & Godfray, 1994). In the class Insecta, several parasitoid was reared, generally its egg, larval or pupal orders are known to include parasitoid species stage. Parasitoids also use many other organisms as hosts (Coleoptera, Diptera, Hymenoptera, Lepidoptera, but in the context of this paper it refers to Lepidoptera. Neuroptera, Strepsiptera and Trichoptera), with ca. 10 % of described insect species being parasitoids (Price, 1975; The term ‘rearing’ refers to a rearing event in which a Mills, 2009). This is the first time that we report on larval host association was established by observation that parasitoid-Lepidoptera associations. Although many more the larva was feeding on the host. The rearing of multiple parasitoids have been reared by CRG members, only 119 conspecific caterpillars from the same host and same parasitoid-Lepidoptera associations have been processed locality at the same time constitutes a single rearing. and are dealt with in a preliminary manner here at family When a single lava was reared on multiple host species, level, prior to undergoing further identification of the these were treated as separate rearings, with the